Electronic distributor of electric signals controlling the operation of internal combustion engine

ABSTRACT

An electronic distributor of electric signals adapted to start operation of the spark plugs or injectors of an internal combustion engine in the desired sequence and if required, for a predetermined lapse of time. This is obtained by means of a static ring counter including as many semiconductor elements as there are tracks leading to the different cylinders. The operation of the engine produces signals in accordance with the speed of rotation so as to enable a main transistor to energize the cathodes of said semiconductor elements in sequence and to operate the corresponding sparking plugs or injectors at the desired sequence. Means are provided to constrain the cycle of energization of the counter components to always start with a predetermined component.

United States Patent Louis A. Mon'petit References Cited UNl'IED STATESPATENTS 3,106,196 10/1963 Woodwardetal.....,.....v

[72] Inventor LEtang-la-ville, France [21] Appl. No. 875,185 [22] Filed123/149 123/32 EA 123/32 EA 123/32 EA 3,324,841 6/1967 Kebbon et3,430,616 3/1969 Glockler et al. 3,433,207 3/1969 Bassot m1"...3,456,628 7/1969 Ba$ot et Primary Examiner-Laurence M. GoodridgeAssislam Examiner-Cort R. Flint Nov. 10, 1969 [45] Patented Oct. 12,1971 {73] Assignee Societedes Procedes Modernes d SOPROM] Les Mureaux,France [32] Priority Dec. 20, 1968 [33] France 179,459 Attomey-Kenyon &Kenyon Reilly Carr & Chapin ABSTRACT: An electronic distributor ofelectric signals adapted to start operation of the spark plugs orinjectors of an internal combustion engine in the desired sequence andif required, for a predetermined lapse of time. This is obtained [54] 0F2y means of a static ring counter including as many semicon- INTERNALCOMBUSTION ENGINE uctor elements as there are tracks leading to thedifferent cyhnders. The operation of the engme produces signals in ac-16 Claims, 5 Drawing Figs.

[52] US. [51] Int. 1

cordance with the speed of rotation so as to enable a main transistor toenergize the cathodes of said semiconductor elements in sequence and tooperate the corresponding sparking plugs or injectors at the desiredsequence. Means are provided 123/32 EA F02ln 51/00, F02b 3/06 [50] Fieldof 123/32 AE, to constrain the cycle of energization of the countercomponents to always start with a predetermined component.

32 EA, 149,148 E PATENTEDOBH2I97I SHEET 2 UF 3 3,612,011

/N\/EN TOR LOUIS A MONDETIT ELECTRONIC DISTRIBUTOR OF ELECTRIC SIGNALSCONTROLLING THE OPERATION OF INTERNAL COMBUSTION ENGINE whenever theengine includes more than one cylinder. In practice, it it necessary toseparate the two parts to be played by the distributor, to wit on theone hand the triggering of the signal-producing means each time and atthe accurate moment at which a signal is required and on the other handthe actual distribution of the signals between the different tracks in apredetermined sequence. It is therefore possible to state that asignal-distributing system should ensure both the cyclic repetition ofthe distribution of the signals and the channelling of the said signalstowards the corresponding tracks at the accurate moment at which thesignal is required on said track.

The conventional ignition means include for instance a circuit breakeractuated by the engine each time an ignition is to be obtained and thedistribution towards the corresponding spark plug is ensured by aprojection revolving over stationary contact-pieces connected with thecorresponding spark plugs. Thus, the moment of ignition and the sequenceof the distribution is defined through mechanical means.

In the case of electrically controlled injection systems, a problemarises that is a signal is sent into an arrangement defining the momentsof injection each time an injection is to be executed and the signalscontrolling the injection are distributed towards the injectors inaccordance with the predetermined sequence of operations of the latter.

In order to prevent the rotary power-feeding contact-pieces which are acause of trouble by reason of the unavoidable wear and of the more orless uncertain contacting between floating parts, it has already beenproposed to resort to distributors with rotary contact-pieces or thelike pulse-generating distributors operating in the desired sequence, nolonger for distributing the power current acting on the injectors or onthe ignition coils but merely for distributing low intensity signals tothe control electrodes of thyristors inserted between the arrangementproducing the ignition or injection signals and the primary of theinjection coil or the injector as the case may be.

Obviously however, such prior arrangements do not provide the advantageswhich may be obtained by an entirely static electronic distribution. Asa matter of fact any electromechanical contacting means even when theyare not subjected to any considerable load produce somewhat uncertainsignals and it is necessary in all cases to standardize said signals andto give them the desired shape. Furthermore, it is a difficult matter tointroduce into such arrangements a lead or a lag depending on theoperative parameters of the engine such as its speed of rotation or theloads to which it is subjected. This may be summarized by stating thatan entirely static arrangement provides a much greater versatility ofoperation while much larger possibilities are afforded for sub jectingthe triggering signal to any desired transformation.

The present invention has primarily for its object to provide anelectronic distributor of electric signals for internal combustionengines wherein a signal-producing system associated with the rotationof the engine produces an electric signal each time an operation is tobe triggered, said signal-producing system being connected with a ringcounter ensuring a cyclic repetition of the operations and including asmany elements as there are tracks for the distribution, each signalcausing a progression by one element of the energization of the ringcounter. I

Further objects of the invention are as follows:

To provide a resetting system associated with the rotation of the enginewhich produces a resetting signal each time the distribution begins afurther cycle, said signal being transmitted to a ring counter such thatthe ring counter is constrained to start its further distributing cyclewith an energization of the first element after receiving the resettingsignal, whatever the actual position of said annular counter may be withreference to each cycle.

According to a modification of the resetting system the annular counterremains locked against operation as long as the resetting signal has notbeen produced.

To provide a distributor adapted to control electromagnetic injectors inthe desired sequence through the agency of thyristors while a furtherarrangement controlling a ring counter triggers said counterindependently of the signalproducing system and without the enginerevolving so as to produce several measured injections before the engineactually starts.

To provide means for transmitting the ignition-controlling signalsincluding a circuit breaker controlling the injection and means fortransmitting resetting signals constituted by a collector inserted in ahigh voltage wire feeding the spark p To provide means for transmittingthe injection-controlling signals and means for transmitting theresetting signals which feed pulses to the annular counter through anelectronic delay arrangement which causes said delay to vary inaccordance with the parameter defining the operation of the engine.

Other features of the invention will appear in the reading of thefollowing description given by way of example only and it should beremarked that all the details although important are not essential, thescope of the invention not being limited otherwise than by theaccompanying claims.

In order to further the understanding of the description, theaccompanying drawings illustrate various embodiments of the invention.

FIG. I is a block diagram of the SignaLdistributing system according tothe present invention.

FIG. 2 is a schematic wiring diagram of a part of an arrangementaccording to the invention including the means defining the duration ofthe control signal.

FIG. 3 is a schematic wiring diagram of a similar arrangement to FIG. 2including lag-producing means and means for resetting and locking inposition the distributing system according to the invention.

FIG. 4 is a schematic wiring diagram of means transmitting controlsignals and connected with the distributor.

FIG. 5 is a schematic wiring diagram of a distributing system accordingto a further embodiment including a counterresetting means and means forcontrolling the distributor independently of the signal-producing meansassociated with the rotation of the engine.

Turning to the drawings, FIG. 1 shows that the 'intemal combustionengine 6 drives a first signal generator 1 which produces a signal eachtime an operation is to be started such as the ignition in a cylinder oran injection of fuel. The second signal generator 2 which is alsoassociated with the rotation of the engine 6 produces a signal each timea complete cycle of operation is at an end and it is necessary to startoperation again with the first cylinder. Such signals are transmitted tothe distributor 3 forming a ring counter possibly through the agency oflag-producing means 7.

The signals produced by the ring counter 3 are fed on the one hand intothe system 4 defining the duration of the signals if the injection offuel is to be controlled, said duration depending on the operativeparameters of the engine which are fed into said system 4. Said signalsproduced by the counter are on the other hand fed into the system 5adapted to distribute the power controlling the injectors 51, 52, 53 54,the signals transmitted by 4 being distributed the injectors inaccordance with the desired sequence of injection. The system 8 controlsthe starting of the ring counter 3 which operates independently of theengine.

P16. 2 illustrates a complete circuit. The transmitter counter 3 andsystems 4 and 5 are shown in said figure within dot-and-dash linedenclosures. The ring counter 3 is constituted by a four-layersemiconductor 11 and three singlejunction transistors 12, 13, 14subjected to a program, this arrangement being applied in theillustrated embodiment to a four-cylinder engine. The anodes of saidsemiconductor elements l1, 12, 13 and 14 are connected with thecollector of a transistor the emitter of which is connected with thevoltage supply while its base receives the positive triggering pulsefrom pulse generator 1 through a connection constituted by the capacitor154 and resistances 36, 37 which are connected so as to form a voltagedivider. The connecting point 59 between the anodes of the semiconductorelements 11, 12, 13 and M on the one hand and the transistor 10 on theother hand is connected with the collector of a second transistor 9through a resistance 38, the emitter of said second transistor 9 beinggrounded whereas its base is connected with the cathodes of thesemiconductor elements 11, 12, 13 and 14 through the potentiometricvoltage-dividing means 19, 20, 21, 22, said base being connected toground resistance 43. The electrode of the four-layer semiconductor 11is biased negatively by its connection with the supply of voltagethrough the resistance 44 but it plays no active part in thearrangement. In contradistinction the control electrode of saidsemiconductor 11 to be biased positively is connected with the collectorof the transistor 9 through a diode 55 and with the cathode of saidsemiconductor 11 through a resistance 39 at the point designated by thereference number 15. Said point 15 is connected with the voltage supplythrough a capacity 40 and the resistances 56 and 47 while the electrodebiasing negatively the single junction transistor 12 adapted to becontrolled by a program is connected with the connecting point betweenthe resistanca 56 and 47. Similarly, the points 16 and 17 in thecircuits of the single-junction transistors 12 and 13 are connected withthe voltage supply through the capacitances 41 and 42 and theresistances 57-48 and 58-49, respectively, and with the negativelybiasing electrodes of the corresponding single-junction transistors 13and 14 controlled by the program through the connecting points betweenthe resistances 57-48 and 58-49, respectively.

The system 4 adapted to define the duration of the injections isconstituted by transistors 28 and 29. The emitter of transistor 28 isconnected with the base of transistor 29. The system 4 further theresistance 46, the programme-controlled single-junction transistor 35,capacitance 27, variable resistances 23, 24, 25, 26 and 34. The variableresistances 23, 24, and 26 are connected with the sliders of thepotentiometric voltage dividing system 19, 20, 21, 22 respectively andthey are also connected in parallel with the variable resistance 34through the corresponding diodes 67, 69, 73, 74. The single-junctionprogramme-controlled transistor is connected through its anode with theconnecting point between variable resistance 34 and the groundedcapacity 27 while its cathode is grounded. its negative controlelectrode is connected with the base of the transistor 28 through thepoint 80 which is also connected with the supply of voltage through theresistance 46. The negative control is connected to ground by resistanceand optionally included by Zener diode 50.

The power-distributing system 5 includes thyristors 30, 31, 32 and 33which are associated respectively with injectors 51, 52, 53 and 54. Thecontrol electrodes for said thyristors 30, 31, 32, 33 are connected ata, b, c, and d, with the cathodes of the corresponding semiconductorelements 11, 12, 13 and 14 of the ring counter through capacitances 81,82, 83 and 84 respectively and resistances 76, 77, 78 and 79 andrespectively. In order to discharge said capacitances 81, 82, 83 and 84after the passage of a pulse, resistances 150, 151, 152, 153 connectedwith the thyristors, are grounded.

The operation of the system is as follows:

At the moment of energization, transistor 10 becomes conductive andenergizes the anodes of semiconductor elements 11, 12, 13 and 14. At thesame time a positive pulse is applied to the control electrode of thefour-layer semiconductor 11 through the diode so that said semiconductorbecomes conductive which makes transistor 9 conductive. Consequently,capacitance 27 begins to charge through potentiometric voltage divider19, the variable resistance 23, the diode 67 and the variable resistance34. Since at the moment of the energization of the system, thesingle-junction programme-controlled transistor 35 is stillnonconducting, a voltage is applied to the base of the transistor 28which becomes conductive so that transistor 29 also becomes conductive.Since the control electrode of thyristor 30 was subjected to atriggering pulse at the moment at which semiconductor 11 becameconductive, the solenoid controlling the injector 51 is energized andproduces an injection of fuel. Said injection lasts until the voltageacross the terminals of capacitance 27 produces an energization of thesingle-junction programmecontrolled transistor 35. When transistor 35conducts the base of transistor 28 becomes grounded and transistor 28 iscut off. This cuts of the current feeding the injector solenoid 51. Thesingle-junction transistor 35 remains conductive as long as thesemiconductor 11 also remains conductive.

When a positive pulse is now applied to the base of transistor 10, thevoltage at point 59 becomes zero, but at the same time the capacitance40 is charged by the voltage supply and keeps transistor 9 conductiveduring a time which is longer than the duration of the pulse acting ontransistor 10. The charging of capacitor 40 causes current to flowthrough resistances 47-56 and the voltage applied to the controlelectrode of the semiconductor 12 decays transiently, which allows it tobecome conductive when voltage returns to the point 59. Resistances 23and 3 1 are chosen so that the current is not sufficient to maintain theconductivity of transistor 35 which therefore cuts off. This causesconductivity of transistor 28 and consequently, upon application of apulse, semiconductor 11 has been cut off and semiconductor element 12has been rendered conductive. The complete cycle may therefore beginover again with a charging of capacitance 27, and an in jection throughthe injector 51 as long as said capacity 27 is not charged. At eachpulse, the next semiconductor element is energized and the precedingsemiconductor is cut off. It should be remarked that only thesemiconductor following that which should be cut off may becomeconductive since only the capacitance inserted between the cathode ofthe semiconductor to be cut off and the control electrode of thesemiconductr which is to be triggered is discharged at the moment of thecutoff. Thus, only said capacitance produces the negative pulse adaptedto trigger the next semiconductor. ln contradistinction, the othercapacitances are charged and can therefore produce no transient signal.

In order to make the cycle begin over again when the last semiconductor14 is cut off, there is no connection between the cathode of saidsemiconductor 14 and the electrode controlling semiconductor 11 andconsequently transistor 9 is cut off when semiconductor 11 is cut off.Thus, when transistor 10 becomes conductive again at the end of thepulse applied to its base, a positive pulse is applied to the electrodecontrolling semiconductor 11 which again becomes conductive so that thecycle begins over again.

it is apparent that the ring counter forms a static distributorcontrolled by a signal which causes said counter to progress by one stepeach time a signal is thus applied to it.

However, in the wiring diagram according to FIG. 2 there is no absoluterelationship between the beginning of the operative cycle of the engineand the starting of the ring counter. As a matter of fact, each timesaid ring counter is energized it has already been triggered oncewithout a signal being applied to the base of the transistor 10.Furthermore, in the case of internal combustion engines the injectionsor the ignitions are controlled in accordance with a predeterminedsequence, each injection or ignition being associated with apredetermined angular position of the engine crankshaft. Now when theengine is at rest, the position of the crankshaft is completelyundefined and it is necessary to reset the distributing system at themoment of the starting of the engine.

To this end a resetting system 2 is provided which produces a signaleach time the engine has finished a complete operative cycle, that is,each time all the injectors have received an order for injection and theseries of injections is to begin over again starting with the firstinjector.

Said resetting system 2 produces a positive signal longer in durationthan the time required for charging capacitors 40, 41 and 42 and saidsignal is applied to the base of transistor 70 (FIG. 3) of which theemitter-collector circuit is inserted in the circuit feeding thesemiconductors 12, 13, and 14. Consequently each time such a signal isapplied to the base of transistor 70 through the point 71 which isgrounded through the resistance 72, semiconductors 12, 13 and 14 are cutof as is transistor 9. None of these elements can be reenergized sincetransistor 70 remains cut off during a period of time longer than thetime required for charging capacities 40, 41 and 42. Consequently,semiconductor 11 is triggered by a positive pulse applied to its controlelectrode through diode 55 and the ring counter then again startsoperating, starting with the first semiconductor 11. It should beremarked that said resetting system does not prevent a number of pulsesfrom being produced with an erroneous setting with reference to thecrankshaft of the engine. This is not objectionable in the case ofindirect control of an injection into the engine but in the case of thecontrol of the ignition or of the direct control of the injection, moreparticularly in Diesel engines, it is essential to prevent a triggeringof the ring counter before the resetting signal has actually reached it.To this end there is provided (FIG. 3) a grounded thyristor 65 connectedwith the resistance 37 through the diode 64, the connecting pointbetween the thyristor 65 and diode 64 being connected with the voltagesupply through resistance 68. Thus as long as said thyristor 65 is notconductive a positive voltage is applied through 36 to the base oftransistor 10, which maintains it in a nonconductive state. Saidthyristor 65 is triggered a positive pulse applied to its controlelectrode at the point 66, which pulse is produced by a signal from theresetting system, which signal is applied simultaneously through thepoint 71 to the transistor 70. Thus, the ring counter remains in anonoperative state as long as the resetting signal has not beenproduced.

In certain cases, it may be of advantage to provide a lead or a lag atthe moment when the distributor is triggered. This can be obtained in avery simple manner with the static distributor according to theinvention. It is sufficient as a matter of fact to insert between thesignal transmitting system 1 and the ring counter 3 an electronic delaysystem 7 (FIG. 3). Said system 7 may be constituted by a monostableflip-flop for instance, which assumes its astable condition uponapplication of the signal produced by the signal transmitter 1 and whichreturns into its stable condition at the end of a predetermined lapse oftime defined by the other parameters introduced into the circuit of themonostable flip-flop 7 at 60 under control of the operative conditionsof the engine such as its speed of rotation, the load applied to it andthe like. The rectangular signal produced by the monostable flip-flop 7is transformed by capacitance 62 and diode 63 associated with resistance61 into a positive peak applied to the base of transistor 10.Consequently, there is a variable lapse of time between the moment ofproduction of the signal by the system 1 and its application to the ringcounter. This results in the possibility of obtaining a lead or a lagthrough an electronic control, either for ignition if the ring countercontrols the primary of the ignition coils or else for injection.

With the arrangement disclosed it is also possible to utilize anignition circuit breaker to trigger the annular counter.

As illustrated in FIG. 4, the ignition circuit breaker 101 controlsdirectly the switching off of current in the primary of ignition coil100. The said primary of ignition coil 100 forms an oscillating circuitwith capacitance 102 so that the signal assumes a very uncertain shape.In order to obtain a positive pulse of a well-defined shape and durationthere is provided an auxiliary circuit connected with the inductioncoils and including in series a diode 103, a resistance 104, anotherresistance 106 and a grounded capacity 107, a grounded capacity 105being connected with the connecting point between the resistances 104and 106. The signals assume the shape shown underneath the illustrationof said auxiliary circuit. The capacitance 107 is charged for apredetermined length of time in accordance with the curve alsoillustrated in FIG. 4. The positive terminal of said capacitor 107 isconnected with the emitter of the single-junction transistor 108 andconsequently the latter is triggered when the voltage across theterminals of capacitor 107 reaches a predetermined value depending onthe characteristic properties of the single-junction transistor 108. Thecapacitor 107 discharges then through an avalanche effect intoresistance 109 and thereis obtained on the base of said single-junctiontransistor 108 a powerful positive pulse also illustrated in FIG. 4,which pulse triggers the ring counter 3.

The ring counter of FIG. 5 is somewhat simpler than in the precedingcase since all the semiconductors in the counting circuit areconstituted by programme-controlled single-junction transistors 11a, 12,13 and 14 while the cathode of the transistor 14 is connected with thenegative control electrode of the transistor 11a in a'manner similar tothat of the connection between the cathodes of the transistors 11012, 13and the corresponding control electrodes of the transistors 12, 13, 14respectively, as provided through a resistance 89 and a capacitance 88.Similarly, all the control electrodes are connected with the supply ofvoltage through the resistances 44, 47, 48 and 49. In order to becertain that the single-junction transistor 11a is always the first tobe triggered upon application of the first signal to the base of thetransistor 10 it is sufficient to break the symmetry of the countingcircuit by grounding the control electrode of the transistor 11a throughthe diode 110 and a resistance 98, which is in parallel with thegrounded capacitance 99. Experience has shown that with such a circuit,the cycle begins always with a triggering transistor lla. It is evenpossible to obtain a resetting of the ring counter by applying simply aresetting signal to the control electrode of said first transistor 11aof the ring counter. It is however possible for the sake of greaterreliability to insert, as in the case of FIG. 3, a transistor 70 in theline feeding the anodes of the semiconductor elements 110, 12, 13 and 14beyond 11a and ahead of the transistors 12, 13 and 14. The control isthen performed as described above; that is, a positive resetting signalis applied at 71 in order to cut off transistor 70. Similarly forpositively cutting off one of the programme-controlled single-junctiontransistors 12, 13 and 14 through the agency of transistor 11a, it issufficient to provide a connection between the cathode of saidtransistor 11a and the capacitances 40, 41, and 42 through diodes whichare not illustrated and which short circuit the resistances 56, 57 and58 respectively.

In contradistinction with the circuits illustrated in FIGS. 2 and 3, thecathodes of the transistors 11a, 12, 13 and 14 are, in FIG. 5, groundeddirectly through resistances 90, 91, 92, 93 respectively in parallelwith the corresponding capacitances 94, 95, 96 and 97. But, obviously,the system 4 defining the duration of injection may be connected in themanner disclosed above. 5

FIG. 5 shows furthermore a modification of the resetting system 2 whichis illustrated in detail and incorporates the system producing theresetting signals, while a special control is provided for the ringcounter 3 independently of the rotation of the engine.

The resetting system 2 is provided with a generator of resetting signalsconstituted by a tubular capacitory collector fitted over the cable 149feeding a spark plug. Said collector is constituted by an inner metaltube 147, and insulating layer 148 and an outer metal tube 146. Thelatter is grounded whereas the inner tube 147 is connected with thecontrol electrode of the programme-controlled single-junction transistorthrough a diode 139. Said control electrode is connected with thevoltage supply through a resistance 144 and is grounded through acapacitance 145. The anode of the single junction transistor 140 isgrounded through a capacitance 142 and is connected with the supply ofvoltage through a resistance 143 whereas its cathode is grounded througha resistance 141. A connection is additionally provided between theelectrode controlling the single-junction transistor 11a and theelectrode controlling the transistor 1411 through a diode 135, aresistance 136 and a capacitance 138, the point of connection betweensaid resistance 136 and the capacitance 138 being additionally connectedwith the supply of voltage through a resistance 137. When a spark jumpsacross the electrodes of the ignition plug, a weak negative pulse isproduced in the capacitory collector 146, 147, 148 and is transmitted tothe electrode controlling the transistor 140 which is then triggered.Consequently, an intense current is caused to flow through saidelectrode which results in a strong negative pulse on the controlelectrode of the transistor 11a which is thus triggered in its turn.Upon triggering of said transistor 140, the capacitance 142 isdischarged and this results again in a cutoff of said transistor. Thepositive pulse which may appear on the base of the transistor 70 at thepoint 71 may be tapped off the cathode of said transistor 140 and fed tosaid point 71.

The auxiliary system 8 controlling the ring counter is associated withthe transmitter 1 producing the triggering signals. Said signalgenerator is connected with the ignition circuit breaker through a diode103, a resistance 104, a capacitance 112 and resistance 113, saidresistance 113 in parallel with the capacitance 114 being connected withthe voltage supply. A resistance 111 grounds the connecting pointbetween the resistance 104 and the capacitance capacity 112.

A programme-controlled single-junction transistor 124 is also provided,the anode of which is connected with the supply of voltage through adiode 119 and a resistance 117, the connecting point between said diode119 and resistance 1 17 being grounded through a resistance 116 and acapacitance 118. The anode of said transistor 124 is further connectedwith the connecting point between the capacitance 112 and the resistance113 through a further capacitance 115. The cathode of said transistor124 is grounded through a resistance 125 and it is connected with thebase of the transistor through the diode 123 and capacitance 122 whichcan discharge through the grounded resistance 126. Lastly the controlelectrode of the transistor 124 is grounded through the capacitance 121and is connected with the voltage supply through the resistance 120 andwith the collector of the transistor 128 through the resistance 127.Said transistor 128 forms part of the auxiliary system 8 controlling thering counter. The emitter of said transistor 128 is grounded and itsbase is also grounded in parallel through a resistance 129 and athermistance 130, but said base is also connected with the voltagesupply through a capacitor 131, a resistance 132 and a pushbutton 134. Aresistance 133 grounds the point connecting the resistance 132 with thepushbutton 134.

In the pulse transmitter 1, the capacitor 112 is normally charged by thesupply of voltage in the direction indicated. When a positive pulsepasses from the circuit breaker to the diode 103, said capacitor 112 ischarged to a voltage which is higher than the supply voltage and thecapacitor 112 transmits its voltage to the anode of the single-junctiontransistor 124 through capacitance 115, which triggers said transistor124 since its control electrode remains at a voltage equal to that ofthe voltage supply. The triggering of transistor 124 transmits apositive signal to the base of transistor 10 through diode 123 andcapacitance 122. However, as soon as the capacitance 118 discharges intothe transistor 124, the latter is cut off again until a further signalis fed to it generated by the ignition circuit breaker.

lt is also possible however to trigger said transistor 124 starting fromthe auxiliary control system 8 by closing the circuit through thepushbutton 134. The capacitor 131 is then charged suddenly anddischarges into the resistance 129 and the thermistance 130 whereby thetransistor 128 is conductive during said period of time. The duration ofthe discharge depends on the value of the thermistance 130, whichdepends in its turn on the temperature of the engine, for instance.During the period of conductivity of the transistor 128 the voltage ofthe control electrode of the transistor 124 decays and the latterbecomes conductive feeding a positive pulse to ring counter 3 which thencauses an injection of fuel. Said transistor 124 remains conductiveuntil the capacitor 118 is discharged, after which it is cut off again.This being done, capacitor 118 is charged again and transistor 124 istriggered again and so on. In other words, as long as the transistor 128is conductive there is a sort of oscillation between triggering and cutoff of programme-controlled single-junction transistor 124. At eachoscillation a pulse is sent into the ring counter, which progresses eachtime by one step.

Consequently, the arrangement disclosed allows injections to be producedwithout the engine revolving. This produces a preliminary injectionbefore the actual starting which is thus furthered.

lt should be remarked that the various parts described may be associatedotherwise than in the manner disclosed with reference to theaccompanying drawings without widening thereby the scope of theinvention as defined in the accom' panying claims.

Iclaim:

1. in an internal combustion engine having a plurality of cylinders andelectrically controlled means associated with each of said cylinders foreffecting combustion therein, and wherein a pulse generator produces aplurality of pulses having a predetermined relationship to the positionof the engine crankshaft, one of said pulses being produced for eachcombustion to be executed in one of said cylinders, improveddistributing means for distributing said pulses to said means foreffecting combustion in said cylinders, comprising in com bination:

a. a static ring counter comprising a plurality of counter elementsequal in number to the number of said cylinders, each elementcorresponding to one of said cylinders and adapted to be energized byone of the pulses produced by said pulse generator;

b. means for successively energizing said counter elements in said ringcounter in response to successive pulses produced by said pulsegenerator;

c. a plurality of switching elements equal in number to the number ofsaid cylinders, each switching element being operatively connected to acorresponding counter element of said ring counter; and

d. means for successively energizing each of said switching elementswhen the corresponding counter element is energized so as to actuatesaid means for effecting combustion associated with the cylindercorresponding to said counter element.

2. The combination set forth in claim 1 further including means forproducing a resetting signal each time the cycle of energization of thering counter components is to begin and means for causing said resettingsignal to start said cycle with a predetermined counter elementindependently of the last element to have been previously energized.

3. The combination set forth in claim 2 wherein the combustion-effectingmeans comprise electromagnetically controlled fuel injectors, andwherein said switching elements comprise a plurality of thyristors equalin number to said injectors and adapted to energize the latter, andfurther including auxiliary means adapted to be energized independentlyof said pulse generator for energizing the elements of said ring counterin sequence to thereby obtain measured injections prior to starting theengine.

4. The combination set forth in claim 2 wherein said engine is of thespark ignition type and said pulse generator comprises the circuitbreaker of the ignition system, said resetting signal producing meansincluding a collector connected to the high voltage lead feeding a sparkplug and adapted to produce said resetting signal.

5. The combination set forth in claim 1 further including means forproducing an adjustable delay in the operation of thecombustion-effecting means.

6. The combination set forth in claim 5 wherein said means for producingan adjustable delay comprises a flipflop circuit connected between saidcombustion-effecting means and said pulse generator.

7. The combination set forth in claim 1 further comprising a resettingsystem controlled by the angular position of the engine crankshaft andadapted to generate a resetting signal each time the cycle ofenergization of the ring counter elements is to begin, means forenabling said resetting signal to start said cycle beginning with apredetermined counter element independently of the last element to havebeen previously energized and means for preventing further operation ofthe counter whenever the resetting signal is not generated afterenergization of the last element in the cycle to be energized.

8. The combination set forth in claim 1 comprising a main transistor thebase of which is adapted to receive a pulse from the pulse generator andwherein the elements of the counter are each constituted by aunijunction electrode-controlled transistor, the anodes of theunijunction transistors being connected in parallel with theemitter-collector circuit of said main transistor so as to be held at azero voltage throughout the duration of said pulse, the cathode of eachcounter element being connected with the combustion-effecting means ofthe corresponding cylinder, a resistance grounding each of saidcathodes, a further resistance and a capacitance connecting each of saidcathodes with the electrode controlling the next successive counterelement, a connection being provided between the cathode of the lastcounter element and the electrode controlling the first counter element,resistances connecting the electrode controlling the counter elementswith a supply of energy and a diode and a resistance capacitance circuitin parallel grounding the electrode controlling the first saidunijunction transistor.

9. The combination set forth in claim 1 wherein the first element of thecounter is constituted by a four-layer semiconductor provided with twocontrol electrodes, the other elements being constituted by unijunctiontransistors each having a control electrode further comprising a maintransistor feeding the anodes of said elements in parallel and the baseof which receives the pulses thereby to hold said anodes at zerovoltage, a second main transistor, a resistance connecting the cathodeof each element with the base of said second main transistor, aresistance grounding said base of said second main transistor, aresistance connecting in series the emitter-collector circuits of bothsaid main transistors, resistances connecting a supply of energy inparallel with the electrodes controlling said unijunction transistorsand the negative control electrode of said four-layer semiconductor, aresistance and a capacitance between the electrode controlling eachunijunction transistor and the cathode of the preceding element, a diodeand resistance connected between the positive control electrode of thefour-layer semiconductor and the supply of energy, a further resistanceconnecting the cathode and negative control electrode of the four-layersemiconductor and resistance and capacitance connections between thecathode of each element and the combustion effecting means of thecorresponding cylinder.

10. The combination set forth in claim 1 wherein said engine is providedwith spark plug fed by high voltage wires, said distributing meanscomprising a main transistor the base of which is adapted to receive apulse from the pulse generator and wherein the elements of the ringcounter each comprise a unijunction electrode-controlled transistor theanodes of the unijunction transistors being connected in parallel withthe emitter-collector circuit of said main transistor thereby to be heldat zero voltage throughout the duration of said pulse, the cathodes ofthe unijunction transistors being connected with the combustioneffecting means of the corresponding cylinders, a resistance groundingeach of said cathodes, a further resistance and a capacitance connectingeach of said cathodes with the electrode controlling the next counterelement, a connection being provided between the cathode of the lastcounter element and the electrode controlling the first counter element,resistances connecting the electrodes controlling the counter elementswith a supply of energy, a diode and a resistance capacitance circuit inparallel grounding the electrode controlling the first unijunctiontransistor counter element, a collector fitted round the wire feedingone of said spark plugs and comprising two coaxial metal tubes separatedby an insulation, means grounding the outer tube and means connectingsaid inner tube and the electrode controlling the first counter elementfor energizing said first element to start each cycle of energization ofsaid counter.

11. The combination set forth in claim 1 comprising a main transistorthe base of which is adapted to receive a pulse from the pulse generatorand wherein the elements of the counter are semiconductors, the anodesof said semiconductors being connected in parallel with theemitter-collector circuit of said main transistor so as to be heldthereby at a zero voltage throughout the duration of said pulse, thecathode of each said element being connected with thecombustion-effecting means associated with the corresponding cylinder, aresistance grounding each of said cathodes, a further resistance and acapacitance connecting each of said cathodes with the electrodecontrolling the next successive counter element a connection beingprovided between the cathode of the last counter element and theelectrode controlling the first counter element, resistances connectingthe electrodes controlling the counter elements with a supply of energy,a resetting system controlled by the operation of the engine and adaptedto start the cycle of energization of the counter elements and includinga further transistor connected between the anode of the first counterelement and the anodes of the other counter elements.

12. The combination set forth in claim 1 comprising a main transistorthe base of which is adapted to receive a pulse from the pulse generatorand wherein the elements of the counter each comprise a semiconductorthe anodes of the semiconductors being connected in parallel with theemitter-collector circuit of the main transistor so as to be heldthereby at a zero voltage throughout the duration of said pulse, thecathode of each element being connected with the combustion-effectingmeans of the corresponding cylinder, a resistance grounding each of saidcathodes, a further resistance and a capacitance connecting each of saidcathodes with the electrode controlling the next counter element, aconnection being provided between the cathode of the last counterelement and the electrode controlling the first counter element,resistances connecting the electrodes controlling said counter elementswith a supply of energy, a resetting system controlled by the operationof the engine and adapted to produce a resetting signal each time thecycle of energization of the counter elements is to begin and means forenabling said resetting signal to start said cycle including asemiconductive element connected with the base of said main transistorso as to keep said main transistor nonconducting until the settingsignal is received.

13. The combination set forth in claim 1 comprising a main transistorthe base of which is adapted to receive a pulse from said pulsegenerator and wherein the elements of the ring counter each comprise asemiconductor, the anodes of the semiconductor elements being connectedin parallel with the emitter-collector circuit of the main transistor soas to be held thereby at zero voltage throughout the duration of saidpulse the cathodes of said elements being connected with thecombustion-effecting means of the corresponding cylinder, a resistancegrounding each of said cathodes, a further resistance and a capacitanceconnecting each of said cathodes with the electrode controlling the nextcounter element, a connection being provided between the cathode of thelast counter element and the electrode controlling the first counterelement, resistances connecting the electrodes controlling the counterelements with a voltage supply and an auxiliary oscillatory circuitadapted to control the counter independently of the pulse generator,including a unijunction transistor and a capacitance, a resistanceconnected between the supply of energy and said capacitance for chargingsaid capacitance,

means for applying to the electrode controlling said unijunctiontransistor a voltage lower than the voltage charging said last-mentionedcapacitance to discharge said capacitance and means feeding the pulsesproduced by said discharge to the base of the main transistor to startoperation of the counter.

14. The combination set forth in claim 1 comprising a main transistorthe base of which is adapted to receive a pulse from the pulse generatorand wherein the elements of the counter are each constituted by asemiconductor the anodes of the semiconductor elements being connectedin parallel with the emitter-collector circuit of the main transistor soas to be held thereby at zero voltage throughout the duration of saidpulse, the cathode of each counter element being connected with thecombustion-effecting means of the corresponding cylinder, a resistancegrounding each of said cathodes, a further resistance and a capacitanceconnecting each of said cathodes with the electrode controlling the nextsuccessive element, a connection being provided between the cathode ofthe last counter element and the electrode controlling the first counterelement, resistances connecting the electrodes controlling the counterelements with a voltage supply, an auxiliary oscillatory circuit adaptedto control the counter independently of the pulse generator including aunijunction transistor and a capacitance, a resistance connected betweenthe voltage supply and the capacitance for charging said capacitance, aresistance connecting the voltage supply to the electrode controllingsaid unijunction transistor, a further auxiliary transistor thecollector of which is connected with said unijunction transistor, meansgrounding the emitter of said auxiliary transistor and a switch throughwhich the base of said auxiliary transistor is connected with thevoltage supply, a resistance and a therrnistance grounding in parallelthe base of said auxiliary transistor to keep the oscillatory circuitenergized as long as said auxiliary transistor remains conductivewhereby the electrode controlling said unijunction transistor is fed avoltage lower than the voltage charging said last-mentioned capacitanceso that said capacitance discharge periodically into the base of themain transistor to start operation of the counter.

15. The combination set forth in claim 1 wherein said engine is of thespark ignition type with spark plugs fed through a circuit breaker,comprising a main transistor the base of which is adapted to receive apulse from the pulse generator and wherein the elements of the countereach comprise a semiconductor the anodes of said semiconductor elementsbeing connected with the emitter-collector circuit of the maintransistor to be thereby held at zero voltage throughout the duration ofsaid pulse and the cathode of each element being connected with thecombustion-effecting means of the corresponding cylinder, a resistancegrounding each of said cathodes, a further resistance and a capacitanceconnecting each of said cathodes with the electrode controlling the nextsuccessive counter element, a connection being provided between thecathode of the last counter element and the electrode controlling thefirst counter element, resistances connecting the electrodes controllingthe counter elements with a voltage supply, an auxiliary oscillatorycircuit adapted to control the counter independently of the pulsegenerator including a unijunction transistor and a capacitance, aresistance connected between the voltage supply and the capacitance forcharging said capacitance a connection between the circuit breaker andthe unijunction transistor to feed the electrode controlling saidunijunction transistor with a voltage lower than the voltage chargingsaid last-mentioned capacitance to discharge the latter and meansfeeding the pulses produced by said discharge to the base of the maintransistor to start operation of the counter.

16. The combination set forth in claim 1 wherein said engine is of thefuel injection type further comprising a timing circuit including twotransistors the emitter of one of which is connected with the base ofthe other transistor, a resistance connecting the base of the said onetransistor with a voltage supply, a further resistance grounding saidbase of the said one transistor, a connection through which the emitterof the said other transistor controls the fuel injectors, an auxiliaryunijunction transistor the control electrode of which is connected withsaid base of the said one transistor and the cathode of which isgrounded, a capacitance one terminal of which is grounded and the otheris connected with the anode of said auxiliary unijunction transistor, anadjustable potentiometric voltage divider connected between said anodeof said auxiliary unijunction transistor and the semiconductor elementsof the counter, said last-mentioned unijunction transistor periodicallytriggering the timing circuit and consequently the operation of theinjectors during the time required for the charging of saidlast-mentioned capacitance in accordance with the setting of saidpotentiometric voltage divider.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,612,011 Dated October 12, 1971 Inventor(s) Louis A. Monpetit It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

On the Abstract page, line 4, "lapse" should be period Column 1, line20, after "of" and before "said" delete the Column 2, line 25,"parameter" should be parameters line 69, after "the" and before"injectors" insert line 73, after "transmitter" insert 1,

Column 3, line 18, after "ground" and before "resistance" insert throughline 43, after "further" and before "the" insert includes line 56, after"control" and before is insert electrode line 64, after "79" and before"respectively" delete and Column 4, line 15, "of" should be off line #2,"conductr" should be conductor U 5 GOVERNMENT PRINTING OFFICE 3969D3GG334 ORM PO-IOSO (10-693 UNITED STATES PATENT OFFICE Page 2CERTIFICATE OF CORRECTION Dated Qgtgbg; 12 1 921 Louis A. MonpetitPatent No. 3,612,011

Inventor(s) It is certified that error appears in the above-identifiedpatent and that said Letters Patent are hereby corrected as shown below:

Column 5,

line 10, "of" should be off line 13, "capacities" should be capacitancesline 32, after "triggered" and before "a," insert Column 6, line 32,after "triggering" and on line 33 before "transistor" insert of Column7, line 26, after "capacitance" delete capacity Column 10, line 5 L,setting" should be resetting Column 11, line 37, discharge" should bedischarges Signed and sealed this 16th day of May 1972.

(SEAL) Attest:

ROBERT GOTTSCHALK EDWARD M.FLETCHER,JR.

Com issio er of Patents Attesting Officer USCOMM-DC 60376-P69 n u scovzmmsm PRIN'HNG syncs may n-ns-zu

1. In an internal combustion engine having a plurality of cylinders andelectrically controlled means associated with each of said cylinders foreffecting combustion therein, and wherein a pulse generator produces aplurality of pulses having a predetermined relationship to the positionof the engine crankshaft, one of said pulses being produced for eachcombustion to be executed in one of said cylinders, improveddistributing means for distributing said pulses to said means foreffecting combustion in said cylinders, comprising in combination: a. astatic ring counter comprising a plurality of counter elements equal innumber to the number of said cylinders, each element corresponding toone of said cylinders and adapted to be energized by one of the pulsesproduced by said pulse generator; b. means for successively energizingsaid counter elements in said ring counter in response to successivepulses produced by said pulse generator; c. a plurality of switchingelements equal in number to the number of said cylinders, each switchingelement being operatively connected to a corresponding counter elementof said ring counter; and d. means for successively energizing each ofsaid switching elements when the corresponding counter element isenergized so as to actuate said means for effecting combustionassociated with the cylinder corresponding to said counter element. 2.The combination set forth in claim 1 further including means forproducing a resetting signal each time the cycle of energization of thering counter components is to begin and means for causing said resettingsignal to start said cycle with a predetermined counter elementindependently of the last element to have been previously energized. 3.The combination set forth in claim 2 wherein the combustion-effectingmeans comprise electromagnetically controlled fuel injectors, andwherein said switching elements comprise a plurality of thyristors equalin number to said injectors and adapted to energize the latter, andfurther including auxiliary means adapted to be energized independentlyof said pulse generator for energizing the elements of said ring counterin sequence to thereby obtain measured injections prior to starting theengine.
 4. The combination set forth in claim 2 wherein said engine isof the spark ignition type and said pulse generator comprises thecircuit breaker of the ignition system, said resetting signal producingmeans including a collector connected to the high voltage lead feeding aspark plug and adapted to produce said resetting signal.
 5. Thecombination set forth in claim 1 further including means for producingan adjustable delay in the operation of the combustion-effecting means.6. The combination set forth in claim 5 wherein said means for producingan adjustable delay comprises a flip-flop circuit connected between saidcombustion-effecting means and said pulse generator.
 7. The combinationset forth in claim 1 further comprising a resetting system controlled bythe angular position of the engine crankshaft and adapted to generate aresetting signal each time the cycle of energization of the ring counterelements is to begin, means for enabling said resetting signal to startsaid cycle beginning with a predEtermined counter element independentlyof the last element to have been previously energized and means forpreventing further operation of the counter whenever the resettingsignal is not generated after energization of the last element in thecycle to be energized.
 8. The combination set forth in claim 1comprising a main transistor the base of which is adapted to receive apulse from the pulse generator and wherein the elements of the counterare each constituted by a unijunction electrode-controlled transistor,the anodes of the unijunction transistors being connected in parallelwith the emitter-collector circuit of said main transistor so as to beheld at a zero voltage throughout the duration of said pulse, thecathode of each counter element being connected with thecombustion-effecting means of the corresponding cylinder, a resistancegrounding each of said cathodes, a further resistance and a capacitanceconnecting each of said cathodes with the electrode controlling the nextsuccessive counter element, a connection being provided between thecathode of the last counter element and the electrode controlling thefirst counter element, resistances connecting the electrode controllingthe counter elements with a supply of energy and a diode and aresistance capacitance circuit in parallel grounding the electrodecontrolling the first said unijunction transistor.
 9. The combinationset forth in claim 1 wherein the first element of the counter isconstituted by a four-layer semiconductor provided with two controlelectrodes, the other elements being constituted by unijunctiontransistors each having a control electrode further comprising a maintransistor feeding the anodes of said elements in parallel and the baseof which receives the pulses thereby to hold said anodes at zerovoltage, a second main transistor, a resistance connecting the cathodeof each element with the base of said second main transistor, aresistance grounding said base of said second main transistor, aresistance connecting in series the emitter-collector circuits of bothsaid main transistors, resistances connecting a supply of energy inparallel with the electrodes controlling said unijunction transistorsand the negative control electrode of said four-layer semiconductor, aresistance and a capacitance between the electrode controlling eachunijunction transistor and the cathode of the preceding element, a diodeand resistance connected between the positive control electrode of thefour-layer semiconductor and the supply of energy, a further resistanceconnecting the cathode and negative control electrode of the four-layersemiconductor and resistance and capacitance connections between thecathode of each element and the combustion effecting means of thecorresponding cylinder.
 10. The combination set forth in claim 1 whereinsaid engine is provided with spark plug fed by high voltage wires, saiddistributing means comprising a main transistor the base of which isadapted to receive a pulse from the pulse generator and wherein theelements of the ring counter each comprise a unijunctionelectrode-controlled transistor the anodes of the unijunctiontransistors being connected in parallel with the emitter-collectorcircuit of said main transistor thereby to be held at zero voltagethroughout the duration of said pulse, the cathodes of the unijunctiontransistors being connected with the combustion effecting means of thecorresponding cylinders, a resistance grounding each of said cathodes, afurther resistance and a capacitance connecting each of said cathodeswith the electrode controlling the next counter element, a connectionbeing provided between the cathode of the last counter element and theelectrode controlling the first counter element, resistances connectingthe electrodes controlling the counter elements with a supply of energy,a diode and a resistance capacitance circuit in parallel grounding theelectrode controlling the first unijunction transistor counter element,a colLector fitted round the wire feeding one of said spark plugs andcomprising two coaxial metal tubes separated by an insulation, meansgrounding the outer tube and means connecting said inner tube and theelectrode controlling the first counter element for energizing saidfirst element to start each cycle of energization of said counter. 11.The combination set forth in claim 1 comprising a main transistor thebase of which is adapted to receive a pulse from the pulse generator andwherein the elements of the counter are semiconductors, the anodes ofsaid semiconductors being connected in parallel with theemitter-collector circuit of said main transistor so as to be heldthereby at a zero voltage throughout the duration of said pulse, thecathode of each said element being connected with thecombustion-effecting means associated with the corresponding cylinder, aresistance grounding each of said cathodes, a further resistance and acapacitance connecting each of said cathodes with the electrodecontrolling the next successive counter element, a connection beingprovided between the cathode of the last counter element and theelectrode controlling the first counter element, resistances connectingthe electrodes controlling the counter elements with a supply of energy,a resetting system controlled by the operation of the engine and adaptedto start the cycle of energization of the counter elements and includinga further transistor connected between the anode of the first counterelement and the anodes of the other counter elements.
 12. Thecombination set forth in claim 1 comprising a main transistor the baseof which is adapted to receive a pulse from the pulse generator andwherein the elements of the counter each comprise a semiconductor theanodes of the semiconductors being connected in parallel with theemitter-collector circuit of the main transistor so as to be heldthereby at a zero voltage throughout the duration of said pulse, thecathode of each element being connected with the combustion-effectingmeans of the corresponding cylinder, a resistance grounding each of saidcathodes, a further resistance and a capacitance connecting each of saidcathodes with the electrode controlling the next counter element, aconnection being provided between the cathode of the last counterelement and the electrode controlling the first counter element,resistances connecting the electrodes controlling said counter elementswith a supply of energy, a resetting system controlled by the operationof the engine and adapted to produce a resetting signal each time thecycle of energization of the counter elements is to begin and means forenabling said resetting signal to start said cycle including asemiconductive element connected with the base of said main transistorso as to keep said main transistor nonconducting until the settingsignal is received.
 13. The combination set forth in claim 1 comprisinga main transistor the base of which is adapted to receive a pulse fromsaid pulse generator and wherein the elements of the ring counter eachcomprise a semiconductor, the anodes of the semiconductor elements beingconnected in parallel with the emitter-collector circuit of the maintransistor so as to be held thereby at zero voltage throughout theduration of said pulse the cathodes of said elements being connectedwith the combustion-effecting means of the corresponding cylinder, aresistance grounding each of said cathodes, a further resistance and acapacitance connecting each of said cathodes with the electrodecontrolling the next counter element, a connection being providedbetween the cathode of the last counter element and the electrodecontrolling the first counter element, resistances connecting theelectrodes controlling the counter elements with a voltage supply and anauxiliary oscillatory circuit adapted to control the counterindependently of the pulse generator, including a unijunction transistorand a capacitance, a resistance connected between the supply of energyand said capacitance for charging said capacitance, means for applyingto the electrode controlling said unijunction transistor a voltage lowerthan the voltage charging said last-mentioned capacitance to dischargesaid capacitance and means feeding the pulses produced by said dischargeto the base of the main transistor to start operation of the counter.14. The combination set forth in claim 1 comprising a main transistorthe base of which is adapted to receive a pulse from the pulse generatorand wherein the elements of the counter are each constituted by asemiconductor the anodes of the semiconductor elements being connectedin parallel with the emitter-collector circuit of the main transistor soas to be held thereby at zero voltage throughout the duration of saidpulse, the cathode of each counter element being connected with thecombustion-effecting means of the corresponding cylinder, a resistancegrounding each of said cathodes, a further resistance and a capacitanceconnecting each of said cathodes with the electrode controlling the nextsuccessive element, a connection being provided between the cathode ofthe last counter element and the electrode controlling the first counterelement, resistances connecting the electrodes controlling the counterelements with a voltage supply, an auxiliary oscillatory circuit adaptedto control the counter independently of the pulse generator including aunijunction transistor and a capacitance, a resistance connected betweenthe voltage supply and the capacitance for charging said capacitance, aresistance connecting the voltage supply to the electrode controllingsaid unijunction transistor, a further auxiliary transistor thecollector of which is connected with said unijunction transistor, meansgrounding the emitter of said auxiliary transistor and a switch throughwhich the base of said auxiliary transistor is connected with thevoltage supply, a resistance and a thermistance grounding in parallelthe base of said auxiliary transistor to keep the oscillatory circuitenergized as long as said auxiliary transistor remains conductivewhereby the electrode controlling said unijunction transistor is fed avoltage lower than the voltage charging said last-mentioned capacitanceso that said capacitance discharge periodically into the base of themain transistor to start operation of the counter.
 15. The combinationset forth in claim 1 wherein said engine is of the spark ignition typewith spark plugs fed through a circuit breaker, comprising a maintransistor the base of which is adapted to receive a pulse from thepulse generator and wherein the elements of the counter each comprise asemiconductor the anodes of said semiconductor elements being connectedwith the emitter-collector circuit of the main transistor to be therebyheld at zero voltage throughout the duration of said pulse and thecathode of each element being connected with the combustion-effectingmeans of the corresponding cylinder, a resistance grounding each of saidcathodes, a further resistance and a capacitance connecting each of saidcathodes with the electrode controlling the next successive counterelement, a connection being provided between the cathode of the lastcounter element and the electrode controlling the first counter element,resistances connecting the electrodes controlling the counter elementswith a voltage supply, an auxiliary oscillatory circuit adapted tocontrol the counter independently of the pulse generator including aunijunction transistor and a capacitance, a resistance connected betweenthe voltage supply and the capacitance for charging said capacitance aconnection between the circuit breaker and the unijunction transistor tofeed the electrode controlling said unijunction transistor with avoltage lower than the voltage charging said last-mentioned capacitanceto discharge the latter and means feeding the pulses produced by saiddischarge to the base of the main transistor to start operation of thecounter.
 16. The combination set forth in claim 1 wherein said engine isof the fuel injection type further comprising a timing circuit includingtwo transistors the emitter of one of which is connected with the baseof the other transistor, a resistance connecting the base of the saidone transistor with a voltage supply, a further resistance groundingsaid base of the said one transistor, a connection through which theemitter of the said other transistor controls the fuel injectors, anauxiliary unijunction transistor the control electrode of which isconnected with said base of the said one transistor and the cathode ofwhich is grounded, a capacitance one terminal of which is grounded andthe other is connected with the anode of said auxiliary unijunctiontransistor, an adjustable potentiometric voltage divider connectedbetween said anode of said auxiliary unijunction transistor and thesemiconductor elements of the counter, said last-mentioned unijunctiontransistor periodically triggering the timing circuit and consequentlythe operation of the injectors during the time required for the chargingof said last-mentioned capacitance in accordance with the setting ofsaid potentiometric voltage divider.